There are several types of commercially-available slash-forwarders that are purpose built to forward woody logging slash and tops from in-woods locations to a landing or road­side pickup for subsequent processing or transportation. These machines include simple

forwarders with bunks for transport of loose logging residue, machines with inverted hydraulic grapples that compress slash in order to increase payload capacity, and forwarders with mechanisms for wrapping slash into large bundles.

Alternatively, a variety of self-feeding chipper-forwarders now exists that are able to pick up and chip logging residue in the woods. Slash is picked up with a hydraulic arm and grapple, self-fed to an in-feed conveyor or feed roller mechanism, chipped, and carried in an internal container to the landing. Because chipper-forwarders densify biomass from logging residues in the woods prior to transport, these machines tend to have higher production rates than slash-forwarders [4].